Achalasia is a rare and benign neurodegenerative disorder characterised by failure of relaxation of the lower oesophageal sphincter and loss of peristalsis in the distal oesophagus. The aetiology is unknown although there may be an autoimmune component. A patient presenting in a GP surgery with achalasia is rare (incidence approx. 0.7 – 1.6 per 100,000; prevalence 3-4 in 1 million). Achalasia typically occurs in adults aged 25-60 years. The male-to-female ratio is 1:1 and less than 5% of cases occur in children.
Patients are likely to present with dysphagia (most common) often with regurgitation, chest pain, heartburn and weight loss.
Since all pathology beyond the fauces relating to swallowing is inaccessible to physical examination, most useful information is obtained from a carefully taken history to discover whether the patient really has dysphagia and where the cause is likely to be situated. Dysphagia is a symptom to be taken seriously and merits investigation unless the cause is obvious such as acute tonsillitis.
Differential diagnosis of dysphagia, listed below, can be divided into:
Achalasia can only be properly diagnosed after endoscopy, barium meal swallow test and manometry. Endoscopy may well appear normal in achalasia, but food residue and a dilated oesophagus may be relevant and noted. If symptoms persist after a normal endoscopy with negative histology to rule out eosinophilic oesophagitis, it may be appropriate to make a referral for a barium swallow test (where a distorted oesophagus and narrowed lower oesophageal sphincter and dilatation above give the “bird’s beak” appearance) if this has not already been undertaken in specialist care.